1 files changed, 44 insertions, 16 deletions

diff --git a/tools/yaml2obj/yaml2wasm.cpp b/tools/yaml2obj/yaml2wasm.cpp
index cf591e16317c..110700d40c32 100644
--- a/tools/yaml2obj/yaml2wasm.cpp
+++ b/tools/yaml2obj/yaml2wasm.cpp
@@ -110,22 +110,52 @@ static int writeInitExpr(const wasm::WasmInitExpr &InitExpr, raw_ostream &OS) {
   return 0;
 }
 
+class SubSectionWriter {
+  raw_ostream &OS;
+  std::string OutString;
+  raw_string_ostream StringStream;
+
+public:
+  SubSectionWriter(raw_ostream &OS) : OS(OS), StringStream(OutString) {}
+
+  void Done() {
+    StringStream.flush();
+    encodeULEB128(OutString.size(), OS);
+    OS << OutString;
+    OutString.clear();
+  }
+
+  raw_ostream& GetStream() {
+    return StringStream;
+  }
+};
+
 int WasmWriter::writeSectionContent(raw_ostream &OS, WasmYAML::LinkingSection &Section) {
   writeStringRef(Section.Name, OS);
+
+  SubSectionWriter SubSection(OS);
+
+  // DATA_SIZE subsection
+  encodeULEB128(wasm::WASM_DATA_SIZE, OS);
+  encodeULEB128(Section.DataSize, SubSection.GetStream());
+  SubSection.Done();
+
+  // DATA_ALIGNMENT subsection
+  encodeULEB128(wasm::WASM_DATA_ALIGNMENT, OS);
+  encodeULEB128(Section.DataAlignment, SubSection.GetStream());
+  SubSection.Done();
+
+  // SYMBOL_INFO subsection
   if (Section.SymbolInfos.size()) {
     encodeULEB128(wasm::WASM_SYMBOL_INFO, OS);
-    std::string OutString;
-    raw_string_ostream StringStream(OutString);
 
-    encodeULEB128(Section.SymbolInfos.size(), StringStream);
+    encodeULEB128(Section.SymbolInfos.size(), SubSection.GetStream());
     for (const WasmYAML::SymbolInfo &Info : Section.SymbolInfos) {
-      writeStringRef(Info.Name, StringStream);
-      encodeULEB128(Info.Flags, StringStream);
+      writeStringRef(Info.Name, SubSection.GetStream());
+      encodeULEB128(Info.Flags, SubSection.GetStream());
     }
 
-    StringStream.flush();
-    encodeULEB128(OutString.size(), OS);
-    OS << OutString;
+    SubSection.Done();
   }
   return 0;
 }
@@ -134,18 +164,16 @@ int WasmWriter::writeSectionContent(raw_ostream &OS, WasmYAML::NameSection &Sect
   writeStringRef(Section.Name, OS);
   if (Section.FunctionNames.size()) {
     encodeULEB128(wasm::WASM_NAMES_FUNCTION, OS);
-    std::string OutString;
-    raw_string_ostream StringStream(OutString);
 
-    encodeULEB128(Section.FunctionNames.size(), StringStream);
+    SubSectionWriter SubSection(OS);
+
+    encodeULEB128(Section.FunctionNames.size(), SubSection.GetStream());
     for (const WasmYAML::NameEntry &NameEntry : Section.FunctionNames) {
-      encodeULEB128(NameEntry.Index, StringStream);
-      writeStringRef(NameEntry.Name, StringStream);
+      encodeULEB128(NameEntry.Index, SubSection.GetStream());
+      writeStringRef(NameEntry.Name, SubSection.GetStream());
     }
 
-    StringStream.flush();
-    encodeULEB128(OutString.size(), OS);
-    OS << OutString;
+    SubSection.Done();
   }
   return 0;
 }